Get off your duff and build something!Training the hand and mind since 1982.

Tuesday, October 11, 2011

NES!

Thanks Chris (my brother in law) for giving me his old NES system version 2. I had one years ago and missed it. I use to have a version 1 and sold it at a yard sale when I was a kid in the 90's and regretted it ever since. Now with all the info on the web I was able to do a couple of modifications, something I couldn't do or had no knowledge of all those years ago.

Mod 1 Lock out chip disable

This mod I did because of the 1 Hz flashing problem with some legit games here are some pics, the lock out was always a pain and caused lots of problems with start up.

Mod 2 Blue LED, give the old system a new look

The Led is tied to +5V on the anode and has a 220 ohm (R5) connected to a 74HCU04AP, I looked up the data sheet on the "04" and the output can sink or source up to 20mA not a problem with the blue led (10mA) with some calculation I figured about 8mA was flow through the LED, fine for me it's still very bright and give a modern look.